Sheet delivery mechanism for stop-cylinder printing machines



SHEET DELIVERY MECHANISM FOR STOP-CYLINDER PRINTING MACHINES Filed July5, 1945 '7 Sheets-Sheet 1 III D 0, 1949 w. G. LAWSON ET AL 2,491,819 4SHEET DELIVERY MECHANISM FOR STOP-CYLINDER PRINTING MACHINES Filed July5, 1945 7 Sheets-Sheet 2 1949 w. s. LAWSON ET AL 91,819

SHEET DELIVERY MECHANISM FOR STOP-CYLINDER PRINTING MACHINES Filed July5, 1945 7 Sheets-Sheet 5 Ja /JAE 6.

IM9 w. G. LAWSON ET AL 2,491,819

SHEET DELIVERY MECHANISM FOR STOP-CYLINDER PRINTING MACHINES Filed July5, 1945 7 Sheets-Sheet 4 Deih 1949 w. G. LAWSON ET AL 2, 91,

SHEET DELIVERY MECHANISM FOR STOP-CYLINDER PRINTING MACHINES Filed July5, 1945 '7 Sheets-Sheet 5 Dec. 23, 1949 W. LAWSON ET AL 2949319819 SHEETDELIVERY MECHANISM FOR STOP-CYLINDER PRINTING MACHINES Filed July 5,1945 'TShets-Sheet 6 LAWSON ET AL SHEET DELIVERY MECHANISM FORSTOP-CYLINDER PRINTING MACHINES -Dec. 20, 1949 7 Sheets-Sheet 7 FiledJuly 5, 1945 Patented Dec. 20, 1949 SHE-ET DELIVERY"M'ECHANISMFOR STOP-CYLINDER PRINTING MACHINES Wilfred: George Lawson and.iFrederickStephenEnsland, ignors,.- shy mesne. assignments; to Alfred Barry .Lakeman,.

J enkins i 1- Chentsey,

London, England Application J-ulyi, 1945;.cSerialaNoie603348 42:

In iGreatBritain August 23; 19.44

,9 Claims ((1101-2761 1 Ther inyentionurelateseto improvements in thesheet delivery mechanisms-of .-a stopecylinder printing ,press, (thatis, apressi-whichbase reciprocating ty-peybed andacylinderrto which a-shee't i of papen-to be printed-is ,ied 93.5 :thenylinder-isrotatingwand ris printed-duningrsuch'rotation; the cylinder being=,::stopped-wh'en-.- the mprinting; has been=completed.,-c1t is,dmii'ngrthis stoppage 50f the iii cylinder that the sheetis removed:from the print V ingicylindermyzthe delivery mechanisms;

Oneiobject of thesinvention 'is to effectstheflif-t ing oftheatailziendeof theEprintedsheetironnthe printing cylinder and toinitiate the removaleoi moya'l'of thelsheet; comprisingsthefimajor:portioii of the cremovaLican iibe ieflici'ently efiected by :thestronger: nr more :positivefiaction of mechanical grippers-::1MO1'e0Y61,'ith6 tr3LVe1 0f the suction gers: need only he meriy short:and the liability *of a sheet being dropped by vthe i'ingers is reducedto a minimum. 1: Further; as the conveyor ean b'e provided :Wibh'i'tplurality-0f sets of mechanical grippers for conveying the sheets awayfromthe printing cylinder and. depositing them on a piling tablefithetravel of the sheets so conveyed can 'be prolonged and: thereby enablethe sheets to dry and to prevent smearing or smudg-ing of 'the printed:matter and the necessitytfor interleaving.

Otheriobjects are to improvetheefiiciencyof th'csuction fingers inoperation, to 'allow for and to :tacilitateiadju'stment eftheopera'ting' mecha- IliSHDOf the :suctionfingerssandmf that of the conveyorxito :suit thezlengthflof lsheet b'eing printed, andiipreferably toensure that when the 'driving mechanism-.iof the-:suctiomfingers"isadjusted,"

simultaneous corresponding adjustment: of the conveyor isefiectedgethereby avoidings-thernecessity for :theiskill and time of themachinezninderf; whichiwouldzbe required'fif separate adjustments:

were required.

.Eunther objects will beiapparen't from the: following description ofone example of sheet deIivJ-i' ery emechanism .accordingrto theinventions;

In the drawingsz,

2 the sheet delivery mechanismepplied, only sufiie cientparts of thepresslbeing indicated toidentify themachine,.=which is well known .intheL Figural is a reariseotional,elevationctaken on the .line II.-II,Eigure1..

Figures. 3 and A. are, respectively, a sideielevation and iarearelevation showing .thesucker .bar, its. valve box and ,other.'-detai1s,.on .a larger scale than Figures -1'. andZ, :the-printingcylinder beingindicated in dot and dash lines.

.Figuresii, 6 andfitaresside views ofsmalLlevers which. are to .bemounted oncthe sucker. ban-end areiherein-shownseparately vfor the sakeof clear-.-

ness. -1- i Eigurze Z8 is -.asidelsectional elevationiof the diaphragm:motor.-. 1 or operating thesmoothersi Figurea is a side-view of oneofthe suction fingers-z.

Finger-V1.0 is az-side "elevation, partly in section, showingisome iofthe-parts in theirrelative =pOSi'r tions, (assumed twhen thesuction:fingers are, givingeup a sheetto the mechanical grippersonatheCOIIMQQTOIZdi Figures 11 and 12 are, respectively, .a'planand afronteview-rof ioneiendiportioneof a gripper-bar andits attachment to achain- Eig uries 13 iandilei are side views -.show-ing.;a camandialgripper bar Withits-actuatin'g lever-in their relative. positions4 when the rmechanical grippers arecpenediandrclosed, respectively.

Figure 15 is a; view:-of the rearendnf the press showingthen-conveyorwithfitsframe bars in section, the counter-balancingdeviceioriheframe barsandrthe-piling table.

i .Referningz'firstaito Figures 'l- 'a-ndw2 the frameswonle -l-cofarstop-cylinderiprinting press supports a printing :cylinder: 2 on ashaita 3 .mountedain bearingszii. Asiris well understoodinthe:art;:theprinting [cylinder :is-zarrestedat the ende-of a;pri1nt-. ing operation.The mechanism :forairiving the cylinderiandziefiectingr its arrest :arenot :shown, as zthey aire well known. ':.-Simi1arly';theisheetfeede ingmeehanisme is omitted, the invention only. being! concerned rwithathesheet: deliverymechae-z nismwhichcwill now be describedzie -A tubularsucker bar 5, whichsis ;closedeat its ends, is mounted torotate-or,-:more= strictlysoscil late about its -1ongit-udina1.axis inhearings 5 and- 'i. Theibearingxfijis screwed to the upper endzof a:Figuresti andrllaia:ogethercconstitutexaiside'eles:

bearings L92: storming; part-seer -a abrackettxifll;

which is fixed to the frame 'fihershaftosi' is co-axial with the shaft 3of the printing cylinder 2. The lever 8 is oscillated by a cam I whichis clamped on a driving shaft I I by a screw I2, as it has to beadjusted or set thereon for a purpose hereinafter explained. The shaftII is driven from the main shaft I29, through gear wheels I2I, I22fixed, respectively, on the shafts I20 and II.

The cam I8 engages with a roller I3 on a lever I4 fulcrumed at I5 andlinked by a rod I6 to a lever I? which is freely mounted to oscillate onthe shaft 3'.

The lever I! has a head I8, Figure 3, for engagement with a flange I8 onthe lever 8. The lever I! is not connected to the lever 8 and makes aconstant oscillation. The lever I'I, however, makes contact with andthrusts the lever 8 in a direction towards the right hand, as consideredwith reference to Figure 1, and for convenience is hereinafter termed acontact lever.

A spring I9 is anchored at I91 and is attached by a cable I99 to thelever 8. When the contact lever I'I recedes, it allows the lever 8 to bereturned by a spring I9, Figures 3 and 4, until arrested by a stop I9I,Figure 10, which is clamped to an arcuate bracket I92 on the frame ofthe press. It is clamped by a screw I93 passing through an arcuate slotI94, so that it can be set in a position required to suit the length ofthe sheet being printed. The stop I 9| determines the initial positionof the lever 8 and will be referred to later on.

The sucker bar 5 is fitted with a number of hollow suction fingers 22having rubber sucker pads 23 for engagement with the tail end of aprinted sheet on the printing cylinder each time the cylinder stops. Thesucker bar 5 extends along the cylinder 2 and the suction fingers 22 arefitted at suitable intervals. Each suction finger 22 preferably has asplit boss 24, Figure 9, embracing the sucker bar 5 and tightened by ascrew 25 when the boss is set on the sucker bar '5, so that a hole 29 inthe suction bar coincides with the passage 21 of the suction finger.Each suction finger preferably has a cock 28 for controlling the passage21.

- In order to render the suction fingers 22 effective, air is withdrawnfrom the sucker bar 5 by any suitable means, such as an exhaust pump,not shown. The air passes out of the suction bar 5 through a hole 29,Figure 4, passage 30, valve box 3! and pipe 32 which is connected to theexhaust pump. The valve box 3| is fitted with a slide valve 33 having anipple 34, Figures 3 and 4, for the pipe 32.

The slide valve 33 has two rollers 35 and 36 for engagement,respectively, with a lever 31 and a cam or stop 38, Figure 1, so that itis reciprocated to open and to cut off suction, as required, by bringingthe nipple into and out of coincidence with a suction hole 34, Figures 3and 4, in the face of the valve box.

The valve box 3| is also fitted with a flap valve 39, Figure 4, pivotedon a pin 43 and controlling an air-inlet hole 40. The flap valve 39 isclosed by a spring 4|, Figure 3, surrounding a rod 42, one end of whichembraces a pin 44 supported between lugs 45, 45 on the valve. The otherend of the rod 42 slides in a lug 41 on the valve box. The lug 45carries a roller 48 for engagement with a cam or stop 49, Figure 1,which is fixed on the framework of the machine. As hereinafterexplained, when the roller 48 engages with the cam 49, the flap valve 39is moved to uncover the air-inlet 48, so that air is admitted to thesucker bar 5.

A raising lever 59, Figure 3, has a split boss 5I, Figure 6, which isclamped by a screw 52 to the sucker bar 5. The raising lever 50 has arod 52' sliding in a lug 53 and surrounded by a spring 54 which tends tothrust the lever 50 upwards and so partly'rotate the sucker bar 5 in onedirection to raise the suction fingers 22. The

7 boss 5! of the lever 50 has two projection 5|,

52" for engagement with the top of the lever 8, to limit the degree ofoscillation of the sucker bar 5. A lowering lever I5I has a split bossI52, Figure 5, which is clamped to the sucker bar 5 by a screw I53. Thelowering lever I5I has a roller 55 for engagement with a cam 55, Figures3 and 4. The cam 56 is adjustably secured to a slotted spur wheel 51 bya screw 58. The spur wheel 5? is free to rotate on the shaft 3, which isco-axial with the shaft 3 of the printin cylinder 2 and meshes with aspur wheel 51, Figure 1, freely rotating on a stud 88 and fixed to asprocket 87 driven by means of a chain 86 hereinafter referred to. Thefunction of the cam 56 is to actuate the lowering lever I5I to rotatethe sucker bar '5, against the action of the spring 54, when theprinting cylinder stops, so that the suction fingers 22 are moved downwith their pads 23 in contact with the tail end of the sheet on theprinting cylinder, and will be referred to later in the description ofthe general operation of the delivery mechanism.

The lowering lever I5I has a second roller 60 for engagement with astationary cam 6|, Figures 2 and 10, mounted on the framework of themachine.

The cam 9| is shaped to ensure that the suction fingers 22 will be heldin the correct position when presenting the sheet to the mechanicalgrippers of a conveyor hereinafter referred to. It is secured to thestationary part I92 by a screw I95 passing through a slot I96 in thecam, so as to allow for adjustment of the cam.

When smoothers are provided to engage with the printed sheet on theprinting cylinder, it is desirable that they be rendered inoperativewhile the sheet is being removed from the cylinder. The smoothers 93,Figures 2 and 4, are carried by a shaft 94 (Figures 2, 4 and 8), mountedto oscillate in lugs 95 on collars 95' clamped to the sucker bar 5. Alever 95, clamped on the shaft 94, is pivotally connected to a rod 9!which is secured to a diaphragm 98, Figure 8, in a chamber 99. The partof the chamber above the diaphragm is in communication with the interiorof the sucker bar 5 through passages I09, MI and holes I92, I03. Thepart of the chamber 99 below the diaphragm 98 is open to the atmospherethrough hole I95.

A spring I94 presses on the upper side of the diaphragm 98 and, when theinterior of the sucker bar 5 is filled with air, the spring I94 holdsthe diaphragm down, so that the smoothers are pressed on to the sheet onthe printing cylinder.

When the air is sucked out of the sucker bar 5, the pressure of theatmosphere on the underside of the diaphragm 98 overcomes the force ofthe spring I94, so that the rod 91 is pulled up and rocks the lever 96,to rotate the shaft 94, so that the smoothers 93 are raised to leave thesheet free to be removed from the printing cylinder 2 by the suckerfingers 22.

A stop disc I95 prevents the rod 9'! rising too far.

The conveyor for taking the sheets from the suction fingers and forconveying them to the end of the printing machine remote from theprinteffect engagement with which have just arrived to receive it. Asthe 5 contact lever ll away from the lever 8,so that the '-lever' B isreturned to its initial position'by its spring l9, and the suctionfingers 22 are in position to move down on to the next sheet as theprinting cylinder 2 completes its rotation and is stopped.

It will be appreciated that the travel of the suction fingers, whilecarrying a sheet to the mechanical grippers of the conveyor, is veryshort relatively to the travel of the sheet in the mechanical gripperson the conveyor.

The long travel on the conveyor gives ample time for the printing ink onthe sheets to dry suificiently, so that smudging of the printed ink isavoided.

Moreover once the sheet has been gripped by the relatively more powerfulor positive mechanical grippers, it can be pulled suificiently oir theprinting cylinder.

' stop-cylinder printing press, having suction devices for engaging withthe tail end of a printed sheet on the printing cylinder of the presswhen said suction devices are in initial position and for initiating theremoval ofthe sheet from the printing cylinder, a conveyor havingmechanical grippers for taking the sheet from the suction devices whenthe printing cycle has been completed and completing its removal fromthe printing cylinder and conveying it away therefrom, means forcarrying the suction devices from their initial position to the conveyorand back to their initial position, and means for arresting saidcarrying means with their suction devices in their initial position,said arresting means being adjustable to regulate the initial positionof the suction devices in accordance to the length of the sheet to beprinted, whereby to 0 regulate the movement of said suction device tothe tail end of the printed sheet.

2. A sheet delivery mechanism for a stop-cylinder printing press,comprising suction fingers for engaging with the tail end of a printedsheet on the printing cylinder of the press and initiating the removalof the sheet therefrom, a sucker-bar carrying said suction fingers, alever supporting said sucker-bar, said sucker-bar being mounted tooscillate on the lever and said lever being pivotally mounted on theshaft co-axial with that of the printing cylinder, a conveyor havingmechanical grippers, means for oscillating said sucker-bar relatively toits supporting lever for the purpose of moving the suction fingers intoand out of their operative positions, and means 'for moving thesupporting lever towards the said conveyor to move the suction fingerstowards the conveyor to allow the mechanical grippers ther of to takethe sheet from the suction fingers to complete the removal of the sheetfrom the printing cylinder after the printing cycle has been completed,and means for arresting said lever in its initial position, saidarresting means beingadjustable to determine said initial position tosuit the length of sheet to be printed, whereby to effect engagementwith the tail end of the printed sheet.

3. A sheet delivery mechanism for a stop-cylinder printing pressaccording to claim 2, including a spring for returning thesucker-barlever to its initial position after each operation, anadjustable stop for arresting the lever in its initial position on itsreturn to suit the length of the sheet being printed, a contact leverfor engaging with the sucker-bar lever and thrusting it against theaction of the spring towards the conveyor, means including a cam foroscillating the contact lever, a shaft for the cam and means i foradjustably fixing the cam on its shaft for the purpose of setting it onthe shaft to suit the length of the sheet being printed. I

4. A sheet delivery mechanism for a stop-cylinder printing pressaccording to claim 2, including a spring for returning the sucker-barlever to its initial position after each operation, an adjustable stopfor arresting the lever in its initial position on its return to suitthe length of the sheet being printed, a contact lever for engaging withthe sucker-bar lever and thrusting it against the action of the springtowards the conveyor,

means including a cam for oscillating the contact lever, a shaft for thecam, means for adjustably fiXing the cam on its shaft for the purpose ofsetting it on its shaft to suit the length of sheet being printed, and asprocket for driving the conveyor, said sprocket being fixed to the camfor the purpose of ensuring simultaneous adjustment of the cam and thesprocket.

5. A sheet delivery mechanism for a stop-cylinder printing pressaccording to claim 2, said means for oscillating the sucker-barrelatively to the lever supporting it, for the purpose of lowering thesuction fingers on to a sheet and of raising them to lift the sheet,comprising a wheel freely mounted on a shaft co-axial with the shaft ofthe printing cylinder, a cam adjustably secured to said wheel, means forrotating said wheel, a follower lever carried by the sucker-bar andhaving a roller engaging with said cam, and a raising lever on thesucker shaft and a return spring for actuating said raising lever.

6. A sheet delivery mechanism for a stop-cylinder printing pressaccording to claim 2, said means for oscillating the sucker-barrelatively to the lever supporting it, for the purpose of lowering thesuction fingers on to a sheet and of raising them to lift a sheet,comprising a wheel freely mounted on a shaft co-aXial with the shaft ofthe printing cylinder, a cam adjustably secured to said wheel, means forrotating said wheel, a lowering lever carried by the sucker-bar andhaving a roller for engagement with said cam, and a raising lever on thesucker-bar and a return spring for actuating said raising lever, saidlowering lever having means for controlling the suction fingers whenpresenting a sheet to the mechanical grippers of the conveyor, saidcontrolling means consisting of a second roller on the aforesaidlowering lever, and a stationary cam for engagement with the secondroller when the sucker-bar supporting lever is moved towards theconveyor.

7. A sheet delivery mechanism for a stop-cylinder printing pressaccording to claim 2, said sucker-bar being provided with a suctionvalve and an air inlet valve, means being providedto open the suctionvalve and to close the air inlet valve when the suction fingers are toengage with a sheet and to close the suction valve and open the airinlet valve when the suction fingers are to release a sheet.

8. A sheet delivery mechanism for a stop-cylinder printing presscomprising suction fingers for engaging with the tail endof a printedsheet on the printing cylinder of the press and initiating the removalof the sheet therefrom, a suckerbar carrying said suction fingers, anendless chain conveyor having mechanical grippers, means for moving saidsuction fingers relatively to the printing cylinder to engage with asheet thereon, means for moving said sucker-bar, when the suctionfingers are in engagement with a sheet, towards the conveyor to enablethe suction fingers to present the sheet to the mechanical grippersthereof, and means for returning said sucker-bar and its suction fingersto their initial positions, a

valve box on the sucker-bar having a suction.

valve and an air inlet valve, the suction valve consisting of a platepivoted on the face of the box to control the suction opening andcarrying a suction pipe nipple, means for moving said plate in onedirection touncover the suction opening and bring the nipple coincidentthere- 2 with and means for closing the air valve when REFERENCES CITEDThe following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 305,798 Cottrell Sept. 30, 18841,141,277 Smith June 1, 1915 1,907,452 Spless May 9, 1933 2,250,657Seybold et al July 29, 1941

